JDBC
This documentation is for an unreleased version of Apache Flink. We recommend you use the latest stable version.

JDBC Connector #

该连接器可以向 JDBC 数据库写入数据。

添加下面的依赖以便使用该连接器(同时添加 JDBC 驱动):

<dependency>
    <groupId>org.apache.flink</groupId>
    <artifactId>flink-connector-jdbc</artifactId>
    <version>1.17-SNAPSHOT</version>
</dependency>

注意该连接器目前还 不是 二进制发行版的一部分,如何在集群中运行请参考 这里

已创建的 JDBC Sink 能够保证至少一次的语义。 更有效的精确执行一次可以通过 upsert 语句或幂等更新实现。

用法示例:

StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
env
        .fromElements(...)
        .addSink(JdbcSink.sink(
                "insert into books (id, title, author, price, qty) values (?,?,?,?,?)",
                (ps, t) -> {
                    ps.setInt(1, t.id);
                    ps.setString(2, t.title);
                    ps.setString(3, t.author);
                    ps.setDouble(4, t.price);
                    ps.setInt(5, t.qty);
                },
                new JdbcConnectionOptions.JdbcConnectionOptionsBuilder()
                        .withUrl(getDbMetadata().getUrl())
                        .withDriverName(getDbMetadata().getDriverClass())
                        .build()));
env.execute();
env = StreamExecutionEnvironment.get_execution_environment()
type_info = Types.ROW([Types.INT(), Types.STRING(), Types.STRING(), Types.INT()])
env.from_collection(
    [(101, "Stream Processing with Apache Flink", "Fabian Hueske, Vasiliki Kalavri", 2019),
     (102, "Streaming Systems", "Tyler Akidau, Slava Chernyak, Reuven Lax", 2018),
     (103, "Designing Data-Intensive Applications", "Martin Kleppmann", 2017),
     (104, "Kafka: The Definitive Guide", "Gwen Shapira, Neha Narkhede, Todd Palino", 2017)
     ], type_info=type_info) \
    .add_sink(
    JdbcSink.sink(
        "insert into books (id, title, authors, year) values (?, ?, ?, ?)",
        type_info,
        JdbcConnectionOptions.JdbcConnectionOptionsBuilder()
            .with_url('jdbc:postgresql://dbhost:5432/postgresdb')
            .with_driver_name('org.postgresql.Driver')
            .with_user_name('someUser')
            .with_password('somePassword')
            .build()
    ))

env.execute()

更多细节请查看 API documentation 。